/**
 * Copyright (C) 2010-2011 Pierre-Yves Ricau (py.ricau at gmail.com)
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not
 * use this file except in compliance with the License. You may obtain a copy of
 * the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed To in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations under
 * the License.
 */
package com.googlecode.androidannotations.processing;

import java.lang.annotation.Annotation;
import java.util.ArrayList;
import java.util.List;

import javax.lang.model.element.Element;
import javax.lang.model.element.ExecutableElement;
import javax.lang.model.element.VariableElement;

import com.googlecode.androidannotations.annotations.Transactional;
import com.sun.codemodel.JBlock;
import com.sun.codemodel.JCatchBlock;
import com.sun.codemodel.JClass;
import com.sun.codemodel.JCodeModel;
import com.sun.codemodel.JExpr;
import com.sun.codemodel.JInvocation;
import com.sun.codemodel.JMethod;
import com.sun.codemodel.JMod;
import com.sun.codemodel.JTryBlock;
import com.sun.codemodel.JVar;

public class TransactionalProcessor implements ElementProcessor {

    @Override
    public Class<? extends Annotation> getTarget() {
        return Transactional.class;
    }

    @Override
    public void process(Element element, JCodeModel codeModel, ActivitiesHolder activitiesHolder) {
        ActivityHolder holder = activitiesHolder.getEnclosingActivityHolder(element);

        String methodName = element.getSimpleName().toString();
        ExecutableElement executableElement = (ExecutableElement) element;

        String returnTypeName = executableElement.getReturnType().toString();
        JClass returnType = holder.refClass(returnTypeName);

        JMethod method = holder.activity.method(JMod.PUBLIC, returnType, methodName);
        method.annotate(Override.class);

        List<JVar> params = new ArrayList<JVar>();
        for (VariableElement parameter : executableElement.getParameters()) {
            String parameterName = parameter.getSimpleName().toString();
            String parameterType = parameter.asType().toString();
            JVar param = method.param(holder.refClass(parameterType), parameterName);
            params.add(param);
        }
        
        JVar db = params.get(0);
        
        JBlock body = method.body();
        
        body.invoke(db, "beginTransaction");
        
        JTryBlock tryBlock = body._try();
        
        JInvocation superCall = JExpr.invoke(JExpr._super(), method);
        for(JVar param : params) {
            superCall.arg(param);
        }
        JBlock tryBody = tryBlock.body();
        if (returnTypeName.equals("void")) {
            tryBody.add(superCall);
            tryBody.invoke(db, "setTransactionSuccessful");
            tryBody._return();
        } else {
            JVar result = tryBody.decl(returnType, "result_", superCall);
            tryBody.invoke(db, "setTransactionSuccessful");
            tryBody._return(result);
        }
        
        JCatchBlock catchBlock = tryBlock._catch(codeModel.ref(RuntimeException.class));
        
        JVar exceptionParam = catchBlock.param("e");
        
        JBlock catchBody = catchBlock.body();
        
        JClass logClass = holder.refClass("android.util.Log");
        JInvocation errorInvoke = catchBody.staticInvoke(logClass, "e");

        errorInvoke.arg(holder.activity.name());
        errorInvoke.arg("Error in transaction");
        errorInvoke.arg(exceptionParam);

        catchBody._throw(exceptionParam);
        
        tryBlock._finally().invoke(db, "endTransaction");        
        

    }

}
